1. Field of the Invention
This invention relates in general to the field of ophthalmological surgical drapes and in particular to apparatus for draping the head and/or head and body of a patient who is undergoing ophthalmological surgery, including means for delivering oxygen to the nose and mouth of the patient.
2. Description of the Prior Art
For surgical operations on the eyes, such as removing cataracts, the patient's face is covered with a drape which usually comprises a sheet or film of plastic material having an opening therethrough in the area of the location of the eye site surgery. When first applied, the drape rests lightly over the mouth and nose of the patient, while the area around the operated eye is glued to the drape. As the surgery progresses, the drape tends to adapt itself more snugly against the nose, mouth, and eye area of the patient due to a variety of factors. One such factor is the natural tendency of the film or plastic to flatten and contour itself about the shape of the patient's face and head. Other factors include the weight of instruments and/or the hands of the nurse or surgical assistant which may inadvertently distort and move the drape about the patient's nose and mouth. This can lead to the unfortunate asphyxiation of a patient who is well covered and over sedated and cannot complain. A patient who is not well sedated will struggle for air and otherwise thrash about in order to improve his or her breathing. Undue body motion can be very detrimental to the surgical procedure. In the latter circumstance, the operating surgeon usually requests more sedation to quiet the patient; however, this leads to a well sedated patient with a further possibility of asphyxiation. Accordingly, sedated patients must be carefully and continuously monitored by an attending anesthesiologist to make sure the patient is still breathing adequately and safely. However, this leads to a well sedated patient with a further possibility of asphyxiation. Accordingly, sedated patients must be carefully and continuously monitored by an attending anesthesiologist to make sure the patient is still breathing adequately and safely.
In order to overcome any of the breathing problems associated with the prior art, a majority of ophthalmologists employ direct intranasal tubing with two long tube extensions that are inserted into each of the patient's nostrils and which supply a constant direct flow of measured oxygen into the patient's nasal canal. These ophthalmologists may also employ an additional tubing apparatus placed below the chin level to draw off the air, which includes carbon dioxide, CO.sub.2, exhaled by the patient which is known to accumulate under the drape. The surgeons who draw off the patient's exhaled air are primarily concerned that the accumulated carbon dioxide content in the exhaled air may give rise to acidosis and possible undesirable hypertension. Where no separate apparatus is used to draw off the accumulated exhaled air containing carbon dioxide, some surgeons will allow the four sides of the plastic facial drape to remain loose so that the exhaled air can readily escape. This latter technique may not always be effective.
With the intranasal oxygen supply apparatus, a continuous flow of oxygen is directly fed to the patient via a fine plastic catheter that has two cannulae extensions, each of which enter deeply into each nostril. The intranasal catheter is held in place by two bands encircled around the ear lobes of the patient. The two intranasal cannulae are further secured to the side of the face with two strips of adhesive tape. Following fixation of the intranasal breathing apparatus to the patient, the draping of the non-surgical portions of the body is then effectuated. It is well known that certain patients do not tolerate the intranasal breathing apparatus. It can cause them to become nervous and irritable, which in turn makes them squirm or thrash about uncontrollably, which movements can seriously interfere with the effectiveness and progress of the surgery. In such instances, the stand-by anesthesiologist administers more intravenous (I.V.) sedation to the patient until all undue movements subside. This has, on certain occasions, resulted in an over sedated patient who then may give no warning sign that the intranasal breathing apparatus has slipped out of the nose, or became disconnected, kinked, or plugged, thereby causing breathing difficulties and even possible unrecognized asphyxiation.
The disadvantages of the intranasal breathing apparatus may be listed in the order of their seriousness as follows: 1) intolerance, and irritation to the nasal mucosa with marked discomfort, 2) the possibility of the small two cannulae extensions of the intranasal apparatus slipping out of one or both nostrils, and thereby subjecting the patient to a silent and unrecognized anoxia, and possible asphyxia, and 3) may induce possible restlessness, irritability, and even arrythmia, all of which may lead to serious cardiac consequences to an aged patient.
In U.S. Pat. No. 4,739,753, by Vrehm, issued Apr. 26, 1988, entitled "Surgical Drape Support and Oxygen Delivery System," the inventor discloses a tubing arrangement which is disclosed and which supplies oxygen to a patient undergoing surgery. An oxygen supply is connected to one end of the tubing while a nozzle is attached to the other end of the tubing in the vicinity of the patient's nose. This invention is a body drape with tubing built in and made relatively stiff to support the weight of the nozzle at the end thereof, as the drape lies over the patient. Thus, the area of the nose of the patient is free of the drape and yet receives a supply of oxygen. In this apparatus, no provision is made for withdrawal of the exhaled carbon dioxide from the patient. Another disadvantage of this apparatus comprises the bulkiness and absence of accuracy of the apparatus which can in addition physically interfere with the critical movements of the operating surgeon; yet another disadvantage is the expense associated with such an apparatus, especially if it is disposable. Most important, it is not an ophthalmological drape.
Accordingly, the main objective of my new ophthalmological drape is to supply oxygen to a patient by indirect means, that is, not as unwieldy and cumbersome as the two canaliculae placed directly into the nostrils of a patient, and yet will assure an adequate, safe, and controlled delivery of oxygen to the patient throughout the surgery.
Another object of my present invention is to provide an ophthalmological drape which provides a surgical mini-mask for escape of carbon dioxide in the expired air of the patient while being completely covered under the surgical drape.
Another object of my present invention is to provide an ophthalmological drape which is proportioned and provided with means to allow the drape to be used by a multitude of different patients having variable sized and contoured faces (long and transverse) and with variable distances between eyes, nose and mouth.
The above-stated objects as well as other objects which, although not specifically stated, but are intended to be included within the scope of the present invention, are accomplished by the present invention and will become apparent from the hereinafter set forth Detailed Description of the Invention, Drawings, and the Claims appended herewith.